Electrical heating appliance



R. IIEIVIP..

ELECTRICAL HEATING APPLIANCE.

APPLICATION FILED FEB. 26| 192i.

R. KEMP.

ELECTRICAL HEATING APPLIANCE.

APPLICATION FILED P55126. 1921.

1,41 1,663. Patented Apr. 4, 1922.

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i vwe/wto 1905er! fem/v 351g, hid @Whom/wij I Wm hw UNITED STATES ROBERT KEMP, F ELMHURST, NE'W YORK, ASSIGNOR TO M. H. AVBAM CORPORATION OF MARYLAND.

PATENT OFFICE.

a co., me., A,

ELECTRICAL HEATING APPLIANCE.

Specification of Letters Patent.

Patented Apr. 4, 1922.

Application tiled February 26, 1921. Serial No. 448,173.

' ances, of which the following is a full, clear,

and concise description. f-

My invention relates to electrical heating Iappliances, and more particularly to such appliances when used for heating currents of air.

More particularly stated, my invention relates to electrical. heating appliances used in connection with portable fans, and employed for the purpose of heating the currents of air from said fan.

While my invention admits of general use, it is of especial value as employed in connection with the form, aggroupment, relative arrangement, and means for supporting of the heating units comprising the principal portion of 'the electric heater, as used with the fan.

Reference i's made to the `accompanying drawings forming a part of this specitication, and in which like reference characters indicate like parts throughout the several figures. Y n

Figure 1 is a fragmentary view, partly in elevation and partly in section, of' the heating unit and parts immediately associated therewith, together with the casing for supporting the same.

Figure 2 is a detail, showing in full and dotted lines the manner of' making the mica sectors forming part of the heating units.

Figure 3 is .a section on the line 3 3 of Figure 1, looking in the direction indicated by the arrows, and showing in addition the fan and certain pai'ts immediately associated cular form, so as to leave an .annular meinber -11. Concentric with this annular member is a larger annular memberi'?. A grating 12 1s so located within the casing as to cover the openings 9, as may be understood from Figures 3 .and 4.-.

The casing 10 is further provided with an I annular member 13 integral with it and concentric to its axis, as may be understood from Figure 3. Another annular member 14 encircles the adjacent portion of the an nular member 13, and is rovided with `a flat annular flange 15, exten( ing outwardly and `occupying a plane crossing the axis of the annular member 13. The annular members 13, 14 are secured rigidly together by a ioint 16, made referably by spot welding. lThe two annu ar members 13, 14, thus secured together, constitute collectively a tubular member provided with the flat annular flange 15.

The casing 6 is also provided with ears 17 each ear having a slot 17a and being bent as indicated in Figures 1 and 3. In this particular instance four of these ears are shown, but the number actually used may be two, three or four, as occasion may req'uire.

Engaging each ear 17 is a small clamping plate 18, having the forni indicated more particularly in Figure 5. This clamping plate is provided with a hole, through which extends awing bolt 19, provided with an expanded tip 20 and extending through theslot 17u. The wing bolt is threaded as indicated in Figure 5, and fitted upon it is a jam nut 21.

A supporting member 22, made in this instance of stout wire, is held in position by two clamping plates 18. By turning the wing bolts 19 the pressure of the clamping plates 18 upon the supporting member 22 may be varied at the will of the operator;

The supporting member 22 carries a motor 23 and a fan 24, for the purpose -of forcing air through the casing 6.

A plate 25, mounted upon the supporting member 22, practically obstructs the adjacent portion of the tubular member comprising the annular members 13, 14. The plate 25 is a baille plate for preventing air from passing through the casing without being heated as hereinafter described.

The wing bolts 19 can not readily become detached from their fittings, owing to the fact that the expanded tips 20 prevent them pair of tongues 28, 29, also extending to-l ward each other. Thus the several pairs of tongues 28, 29 are a little further from the center than is the case with the several pairs of tongues 26, 27. The various pairs of ton es 26, 27 may be considered as groupe roughly into the form of acircle, and the various pairs of tongues 28, 29 may be considered as similarly grouped into an-l other circle Vof slightly larger diameter. By this arrangement the pairs of tongues 26 27 are staggered relatively to the pairs of tongues 28, 29, so that the strength of the annular flange 15 is conserved to better advantage than would ordinarily be the case. In the arrangement just described no two of the tongues are crowded so closely togather as to unduly reduce the strength of the adj acent portion of the annular flange 15.

The casing 6 is also provided with a number of tongues 30 inte ral with it and each having a comparative y narrow portion 31 bent backwardly or outwardly, as indicated in Figure' 3. Each tongue 30 with its revertin portion 31 constitutes practi? cally a hoo and inits entirety is struck or stamped out ofthe sheet metal of the casing, so as to leave openings 32. The tongues 30 are in substantially the same plane as the annular flange 15,' as may be understood from Figure 3.

I provide a number of flat cores 33, each made of sheet mica. These cores can be continuously stamped or pressed from small sheets 34, of sheet mica, as indicated by dotted lines in Figure 2. Each core 33 is provided with a substantially central opening 35, having the proximate form of a triangle. Each core is further provided with two holes 36, 37, disposed adjacent its ends and with a slot 38, located between the hole 37 and the adjacent end portion of the core.

Each core 33 carries a winding 39 of resistance wire adapted to be heated by the passage of an electric current through the winding. Connecting wires 40, 41 are used for connecting up the windings with each other.

In order to mount the cores in position they are laced within the casing as indicated in igure 1. First the tongues 3l are left extending upwardl and the cores are so placed in osition t at each tongue 31 extends thi-ou a slot 38. This done the ton es 31 are nt outwardly, as shown in igures 1 and 3. The inner or narrow and from the latter a wire 45 leads to a binding post 46, this binding post being by means of a short wire 47 connected with the nearest one of the resistance windings 39. The socket 42 is further provided with a contact member 48, and with a bindin post 49 connectedtherewith. A screw p ug. 50, which may be of the usual constructlon, is fitted into the socket 42 and is adapted to coact therewith in the manner well known in this art. Connected with the screw plug 50 are a pair of insulated wires 51, 52.

Another pair of insulated wires are shown at 53, 54, and extend into the casing 6 through an eye 55 of insulating material. The wire 53 leads to a binding post 56 carried by one of the cores 33, and the wire 54 leads to the binding post 46 above mentioned.

Anotherwire 55 .is connected with the binding post 49 carried by the socket 42, and with a binding post 56, with which one of the cores 33 is provided. The core provided with the bindin post 56 is preferably located about haltvay between the two cores serving as terminals for the heating e-lements.

The wires A51, 52 are connected with the electric motor 23, used for driving the fan 24. The supply wires are the wires 53, 54, and they may be connected 'with any wall plug or other convenient source of electrical supply, suitable'for the purpose.

A circuit may be traced through the heat' ingl elementsj and parts immediately associated therewith, as follows:

Source of electricity (not shown) Win53, binding post 56, through six heating units to the binding post 56; here the current divides, a portion pa'ing through wire55. binding postI 49, contact member 48, wire 51, to electric motor 23, wire 52, sleeve 44, wire 45, bind-ing to source of sup Another circult may be traced as follows:

Source ofelectricity (not shown), wire 53, binding A-post 56, then in series through all of the resistance units, to binding post 46, thence through wire 54 back to source of electricity.

The difference' between the two circuits just traced is due to the action of the wire 55, which acts as a shunt for supplying a portion of the current to the electric motor 23. For this purpose the electric motor is supplied with a current havingv a resistance equal to that of one-halfthe total number of the resistance units,- connected in series with each other.

post 46 and wire 54, back If the plug 50 be removed, all ot the cu rrent used will flow through all of the resistance units. in series with each other. but in this event no current is supplied to the electric motor 23. and as a consequence the t'an is idle.

'lhe improved heating unit t'orining a pai't of inv invention presents a. considerablel numb; r ot distinct advantages. The niica coi'es are of such form that they can be made up either from good stock .material -or .from scrap material more or less irregular in torni. as desired. rlhe iiioiintings t'or the cores are quite strong and reliable. and yet they are made in the formation of the casing. so that no extra material is required. and no additional parts aie needed, in their manufacture. In fact nearlyiall ot' the t'astenlings employed in the entire device are ,made troni integral portions ot' the casing. lhe distribution ot' the various tongues and other paits used as fastening members is such as to conserve the. sheet mate "al, and to enable it to retain a maximum ot" its strength.

The separate heat-ing units are readily accessible for purposes of inspection` repair and renewal. They are readily accessible as individual, separate units` or as. a coinpletel group of units. The several mica cores have each a considerable heating surt'ace`v so apportioned and located as to heat the air as far as practicable uniformly throughout. rlhe openings 35, and the spaces between consecutive cores. are easily apportioned .so that the cores will present just enough obstruction to the air current to battle the air sut'- ticient-ly for purposes of heating it unit'ormly throughout.

rlhe torni of the core is such that the resistanceI winding carried by the core is as tar as practicable exposed uniformly to the cooling action ot the air current-s. In other words. the tendency is to enable practicallyA all portions ot' the resistance winding to do equal amounts of work in heating the air.

I do not limit in vselic to the precise mechanisni shown. as. variations may be made therein without departing from my invention. the scope offwhich is commensurate with my claims.

Having thus described my invention` what I claim as new and desire to secure by Ilettcrs Patent is as follows:

1. In a device of the character described. the combination of a casing made ot sheet material and provided with a substantially tubular portion and with a substantially circular portion ot' greater diameter than said tubular portion and concentric thereto. said circular portion being provided with a tongue of sheet material integral with it. and a heating unit provided at one of its ends with a slot for receiving said tongue in order to support said heating unit at the end thereof adjacent said tongue. and means for supporting the other end of said heating unit. upon said substantially tubular portion.

2. In a. device of the character described, thecombination of a casing made of sheet material and provided with a substantially tubular portion and with av substantiall circular portion ot' greater diameter than said substantially tubular portion` said substantially tubular.portion being provided with a. pair ot' tongues extending from it and made of sheet material, and a heating unit supported at one of its ends upon said substantially circular portion, the other ot' its ends being inserted between said pair of tongues and thus supported by said substantially tubular portion.

3. In a device of the character described, the combination ot' a. casing provided with a substantially tubular portion and with. a substantially circular portion ot greater diameter, than said substantially tiibiilai' por tion` and a plurality ot' heating units located within said casing, each heating unit comprising a sector ot' insulating sheet material and a heating element wound upon said sector` the sector being supported at one ot' its ends by said substantially tubular portion and supported at its other end by said substantially circular portion.

4. In a device ot the character described, the combination ot' a casing made ot sheet material and provided with a tubular member and with a pair o't' tongues ot sheet mateiial extending from said tubular member, a heating unit located within said casing and comprising a core Iot insulating material and a heating winding carried by said core, said heating winding engaging said pair of tongues and being at one of its ends supported thereby. and` means tor support-ing this other end from the casing.

5. Ina device ot the character described, the combination of a casing provided with a substantially 4tubular member located centrally thereof. said substantially tubular member having an annular fiange and having tongues integralfwith said flange and arranged in pairs, and a plurality ot' heating units each comprising a core of insulating material and a winding carried by said core, each coie being supported in part by a pair of said tongues.

6. In a device of the character described, the combination'of a casing provided with a substantially` tubular member, the tubular member having a flange of sheet material of annular form extending from it and provided with tongues arranged in pairs, the tongues of one pair being staggered relatively to the tongues ot' another pair in order to conserve the strength of the material of the annular ange. and a plurality of heating units each comprising a core of sheet material and a winding carried by said core, each core being supported in partby one pair of said tongues.

7. A heating unit comprising a single piece of sheet mica having the general form of a sector and provided with a substantially central opening, said piece of sheet mica being further provided with a pair of oppositely disposed ends and with holes lo. cated adjacent said ends, and a` Winding carried by said piece of sheet mica and provided with portions extending through said holes.

8. A device of the character described, comprising a motor, a supporting member secured thereto and having the form of la. stout wire, a casing provided with ears adapted to be engaged by said supporting member, clamping plates for pressing said supporting member against said ears, wing bolts for forcing said clamping platesv againstsaid supporting member, and means for connecting said wing bolts with said ears.

9. In a device of the character described, the combination of a casing made of sheet metal and provided with tongues integral with it, a tubular member carried by saidcasin and provided with an extending portion aving the form of an annular ange, said flange being provided with tongues in- .tegral with it, and a number of heating units grouped about said tubular member and extending radially outward, each heating unit restingat one of its ends upon said flange and being engaged by a. pair of said last mentionedV tongues, and resting at its opposite end upon one of said first mentioned tongues. v

10. In a device of the character described, the combination of a substantially circular casing and a plurality of heating units mounted upon said casing and extending radially inward therefrom, each heating unit comprising a core of sheet material having the general form of a fiat sector, and a resistance member wound around said sector.

11. In a device of the character described, the combination of a casin made of sheet material and provided wit tongues integral with said sheet material and partially severed therefrom, and a plurality of heating unitsV connected with said tongues and extending radially inward from said casing.

1.2. A heating unit comprisin a sector'of sheet micayserving as a core, an a resistance winding encircling. said sector and supported thereby.

13.`A heating unit comprising a sector of insulating sheet material, -said sector being provided with an opening of approximately triangular form, and a heating winding mounted upon said sector and extending across said opening.

14. A heating unit comprising a core of sheet mica havin the proximate form of a sector and provi ed with an opening, and a heating winding mounted upon said core and extending across said opening.

15. A heatingunit comprising a core made of sheet mica and having the form of a. sector, said core being provided with holes extending through it, and a heating member wound upon said core and extending through said holes.

16. A heating unit comprising acore made of sheet insulating material and having the form of a sector, said core being provided with a slot for4 facilitating its support in a heating apparatus, and further provided with holes, and a heating member wound upon said core and extending through said holes. i

17. A heating unit comprising a air of annular casing members one of w ich is concentric vto lthe other, each of said casing.

therein. n

ROBERT KEMP. 

